sfHover = function() { 
    var sfEls = document.getElementById("nav").getElementsByTagName("LI"); 
    for (var i=0; i<sfEls.length; i++) { 
        addEvent(sfEls[i], "mouseover", function() { 
            this.className+=" sfhover"; 
        }); 
        addEvent(sfEls[i], "mouseout", function() { 
            this.className=this.className.replace(new RegExp(" sfhover\\b"), ""); 
        }); 
    } 
} 
 
function addEvent(el, name, func) { 
    if (el.attachEvent) 
        el.attachEvent("on" + name, func); 
    else 
        el.addEventListener(name, func, false); 
} 
 
addEvent(window, "load", sfHover);